Furnace



satented Aug. 16, 1927.

UNITED STATES PATENT OFFICE.

JOHN' F,v BAKER, OF MANSFIELD, OHIO, ASSIGNOR T0 WESTINGHOUSE ELECTRIC'MANUFACTURING COMPANY, A. CORPORATION OFIPENNSYLVANIA.

immuun.

Application med my 27, 192e. seriai Ndlzawa.

My invention relates to a furnace and particularly to a `rotary furnacehaving automatic discharge means.

An object of my invention is to provide in a furnace having a conve er,an efficient means for periodically e ecting the discharge of materialfrom the conveyer.

Another object of my invention is to provide in a furnace having arotary conveyer with a hearth-tray thereon, a pneumatically operatedram, controlled b the conveyer, forl periodically tilting t e hearthtrayto discharge heat-treated material therefrom.

Other objects of m invention will be apparent from the disc osure.

In practicing my invention according to the presen-t disclosure, Iprovide, in a furnace, a conveyer having tiltable hearth-trays thereonand pneumatically operated means, controlled by the movement of theconveyer, for periodically tilting the trays to discharge heat-treatedmaterial therefrom.

The structure of the furnace, including the conveyer andthehearth-trays, is somewhat similar to the structure of the furnacedisclosed in my copending application, Serial Numberk 117 ,937 filedJan. 23, 1926. In the present form of my invention, however, theconveyer is designed to operate .continuously instead of intermittently,although, of course, by providing a control means similar to that shownin the abovementioned application, the conveyer disclosed in the presentapplication may also be operated intermittently.

In the drawing, which shows, by way of illustration, an embodiment of myinvention, Figure 1 is a vertical sectional view of a rotary furnace,with my pneumatically operated tilting means operatively connectedthereto, and

Fig. 2 is a means.

Referring to the drawing for a more complete descrlption of myinvention, a furnace 10 is provided with outer walls 12 and inner wallsof refractory insulating material 13,

the furnace being preferably of annular form and having an annularchamber 14 therein. Suitable supports 15 are provided.

Means for heating the furnace are provided. As a convenient form of suchmeans, electric-resistor members 16 may be positioned in the chamber14,v and suitably sediagram of the dielectric control cured to the wallsthereof. i These resistor ymembers are electrically connected to asource of energy (not shown).

An annular passage-way or run-way 18 is provided in the bottom ofthefurnace. A rotary annular hearth or conveyer 19 is ositioned in saidannular passage-way an is rotatably mounted on a track 20 by means ofwheels 22 that are rotatably mounted on lugs 24, the lugs 24 beingconnected with the metallic base member 25 of the conveyer 19. Theconveyer 19 has a lsuitable insulating portion 26 that is mounted on the.base lmeurber 25.

Suitable means for driving the conveyer are provided and comprise a.rack 30 that may be integral with the base member 25, a gear wheel 31meshing therewith and mounted on a shaft 32 that is rotatably mounted ona bearingsmember 33.

At the opposite end of the shaft 32, a bevel gear-wheel 34 is rigidlysecured to the shaft and meshes with a bevel gear-wheel 36y that isrigidly secured to a vertical shaft 37. This vertical shaft is rotatablymounted in'suitable bearin members 38.

A bevel gear-w eel 39 is rigidly secured to the upper end of theVertical shaft and meshes with a bevel gear-wheel 40 that is rigidlysecured to the shaft 41 of a worm gear speed-reduction unit 42. Shaft 98connects this speed-reduction unit to a motor 99 and the motor is, ofcourse, conneced to a suitable source of eer A plurality ofheartsupports 43 are secured to the insulatin portion 26 of the :onveyer19. Each of t ese hearth-supports hasv a hearth-tray 45 so connectedthereto, by a pivotal joint 46, as to permit tilting of the hearth aboutthe joint.

Means are provided to hermetically seal the spaces between the conveyer19 and the walls ofthe run-way 18. Such means may consist of annularchannel members 48 that are secured to the base member 25 at their 100edges and are adapted to contain sand or other sealing material. A pairof concentric flange members 50 are secured to the bottom of the furnaceand extend into the sand in the corresponding channel members.

A dischar e outlet 52 for the furnace is provided an preferably extendsbeneath the surface of the oil or other quenching me dium in the quenchtank 53. This outlet v.is adapted to receive heat-treated material that110 is periodically discharged from the hearthi ,hearth-tray 45 at itsinner or non-pivoted end. The piston-rod 55 has a piston 59 secured toits lower end that is slidably positioned in a cylinder 60. Thepiston-rod is maintained in a normally retracted position by thespring62. An air-conduit 64 has one end connected to the lower end of thecylinder 60 and the other end connected to the middle chamber 69 offanair-valve housing 66. The air-valve housing has a pair of partitions 67for dividing the house into three chambers, consisting of the chamber65, chamber 6.9 and chamber 70.

The partitions 67 have valve-seats 72 and 73 therein that are adapted toreceive valves 74 and 75, respectively.- The'valves 74 and 75 arerigidly secured to a valve-rod 76 that has an electro-magnet or4 coremember 78 secured to the top thereof. The valve 74 is normallymaintained Seated by means of a spring 80.' A. pipe 82 leads from thechamber to a suitable source of compressed air.

The chamber communicates with the outside atmosphere by means of anopening 84. In the position shown, it willmbe 0bvious, by looking at thedrawing, that access of the compressed air to the cylinder 60 will beprevented, and the piston 59 is, therefore, maintained in its lowest orretracted position by spring 62.

For energizing the electro-magnet 78, a coil or solenoid 90 is provided.This coil 90 is electrically connected to a-main 92 and to a brush 94,as shown in Fig. 2. A second brush 95 is electrically connected to amain 96. A series of contact members 97 are insulatedly mounted on oneof the members 48. Fig. 2 shows both brushes in engagement with acontact member 97. The number of brushes is the same as the number oftrays. In this position, an electric current will flow through the coil90. The contact members 97 are so located that a hearth tray 45 will beopposite to the discharge outlet `wehen the brushes engage one of saidmem- When the motor 99 operates the gear 42), it will drive the conveyer19 by means of the gearing previously described. This will .cause .thehearth-trays 45 to travel through the chamber 14 that is heated by meansof the resistor members 16. The material placed on the hearth-trayswill, therefore, be heat-treated. It will be obvious that the conveyer19 will be continuously moving after the motor 98 is started.

When a tray, having heat-treated material thereon, arrives at a positionopposite the discharge outlet 52, a contact member 97 will engage thepair of brushes 94 and 9:5 and thus close the ycircuit through the coil90. This will cause the valve-rod 76 to move downwardly because oftheaction of the electro-magnet 78. This closes the valve 75 and opensvalve 74, thus permitting compressed air to flow into the lower end lofthe cylinder 60 and forcing the piston I59 upwardly against the actionof spring 62. 'This will cause the roller bearing 57 to engage with ahearth-tray 45 that is to be dumped, and the hearth tray will be tiltedto the position shown in dotted line in Fig. 1, thus dischargingmaterial therefrom into the discharge outlet 52, through which the,material will fall into the quench tank 53. The roller bearing 57minimizes the friction of the hearthtray with the ram 55. 4The contactmembers 97 are, of course, of such length as to maintain the tra 45 intilted position for a suiilcient length o time to ei'ect a discharge ofmaterial therefrom.

The continued rotation of the conveyer will carry the contact member 97out of engagement with the brushes 94 and 95., thus opening the circuitthrough the solenoid 90 and deenergizing the core member 78. This willpermit the spring 8O to force the valverod 76 upward and seat the valve74 again, thus cutting-off `the air supply .from the cylinder 60. Thevalve 75 will be unseated and will permit the escape of air from thecylinder to the outside atmosphere. The spring 62 will then return thepiston 59 to its retracted position. This will permit the tray 45 toreturn to its normal position.

Charging of the empt tra may be ef fected through a suita le c argingdoor (not shown).

It is obvious that my invention could be applied to a furnace in whichthe conve er was not rotary. It is also obvious t at other means thanthat shown could be used for controlling the operation of the ram andfor varying the time cycle between successive dumpings of the trays 45,.

While I have shown and described, for purposes of illustration, a.particular form of my invention, it may, f course, be embodied in vother forms without departing from the spirit and scope thereof, as setforth in the appended claims.

I claim as my invention:

1.v In a furnace, the combination with an annular hearth, a plurality oftrays on said hearth, and means for effecting movement'A of said hearth,of a pneumatic rain the operation of which is initiated by the movementof the hearth for successively tilting said trays.

2. In a furnace, the combination with an annular hearth, a plurality oftrays on said lio 1,ess,eos

hearth, and means for eecting movement of said hearth, of neumatic meansoperative at definite perlods for effecting a tilting movement of saidtrays in sequence.

3. In a furnace, the combination with an annular hearth, a pluralit oftrays on said hearth, and means for e ecting movement of said hearth, ofpressure-actuated means controlled by the movement yof said hearth forsuccessively tilting said trays.

4. In a furnace, in combination a conveyer, a material-receiving traysecured to said conveyer, means for effecting continuous movement ofsaid conveyer, 'pneu-l matic means sitioned beneath said fur-4 nace forperi ically electing the discharge of material from said tray.

5. In a furnace, in combination a conveyer, a tray ivotally secured tosaid conveyer, means or continuously driving said conveyer, pneumaticmeans for operating a piston 4to periodically tilt said tray, theoperation of said pneumatic means being controlled by the movement ofsaid conveyer.

In testimony whereof, I have hereunto subscribed my name this 13th dayof July,

l JOHN F. BAKER.y

